# 循环，利用range
if __name__ == '__main__':
    rangeList = list(range(10))
    print(rangeList)

    sum = 0
    for x in rangeList:
        sum += x
    print(sum)

    sum = 0
    n = 99
    while n > 0:
        sum = sum + n
        n = n - 2
    print(sum)

    rangeList = [5, 4, 3, 2, 1]
    for i, k in enumerate(rangeList):
        print(i, " ", k)
